Enhancing buildings with living green facades not only looks great but is a natural way to regulate inside temperatures and reduce energy consumption. But first you need to know a lot about the structures needed to maintain these ambitious environmental installations.
To achieve stunning, cascading greenery takes a carefully thought-out framework of wires and rods, mixed with botanical know-how to keep the whole thing up and thriving.
An Australian company that has achieved a reputation as a highly regarded business is Tensile Design and Construct. It’s responsible for many of Australia’s most notable biophilic projects including Platinum Tower in Melbourne and Sydney’s foliage-covered Central Park.
A first of its kind globally, Central Park’s iconic green facade includes over 15 kilometres of steel cable and rods supporting more than 2500 climbers and vines, which together create an unforgettable impression.
Vance Apartments, Harold Park, Sydney
Eve Apartments Erskineville, Sydney
It’s no surprise this work captured the attention of other big facility owners. In 2020 the company was called in to create the perimeter fencing for Taronga Zoo’s new lion enclosure, a project that combines the obvious need for strength and impenetrability with good visibility for guests and adaptability of construction.
Director Peter Bottero founded Tensile 11 years ago and now employs 20 people, with offices in both Sydney and Melbourne and construction partners spanning from Perth all the way to Auckland.
Tensile is also partnered with renowned Swiss architectural rigging firm, Jakob Rope Systems, which means it can deliver the best in European-manufactured products to the Aussie market, including the highly versatile Webnet and Greenkit mesh systems.
Bottero explains that as well as using the best products, his company offers industry-leading solutions in three main areas — barriers and fall protection, art and contemporary projects, and of course botanical encompassing green facades and hanging gardens.
Tailored solutions need to consider things like light, wind and plant selection
The company works with clients, primarily architects and government agencies, to offer tailored solutions that with green installations, consider factors like light and wind, plant selection and expected outcomes such as ongoing maintenance.
“We’ve done our job right when our stuff disappears,” Bottero says. “When you can’t see what we did because it’s covered in plants.”
Despite the obvious visual benefits, Bottero recognises the importance of making a strong business case to drive the uptake of green facades. Among the huge incentives, he says, is the improved thermal performance of green walls – where many show 300 per cent improvement on normal glazed-window exteriors. It’s a strong sustainability metric that sits well alongside the aesthetic impact.
“Simple things like heat-island effects; Central Park on its own isn’t going to do anything, but if you start to throw a couple of buildings like that up in close proximity to each other, you will start to get the benefit.”
Clients so far include Lendlease, Multiplex, Junglefy, Fytogreen and most of Australia’s major capital city councils.
The company is looking to make botanicals a larger part of its business, and to do so in a research-based way that delivers the maximum potential benefits to the built environment while avoiding pitfalls.
There are pitfalls and you need to know how to avoid them
From the very first green facade installation in Australia on Melbourne’s CH2 building, keeping suspended flora alive and well has been a challenge, and there’s plenty of anecdotal evidence of where great intentions come unstuck.
You need good collaborators, to start with
But Bottero says Tensile now has the broadest range of knowledge in Australia on the subject, in part due to an ongoing collaboration with key industry experts and Melbourne University’s horticulture department.
The Central Park project involved a steep learning curve. There were lessons there that nobody had anticipated, Peter says, from what type of plants could survive the conditions to how they impact load and structure.
“Being a structural company first and foremost, we asked ‘when a wind hits a leaf, how much load passes through the leaf into the stem onto the cable into the building?’ No one knew and so we stuck plants in a wind tunnel to figure it out,” he says.
“And to my knowledge we’re still the only company in the world that has that data. So, our journey through the botanical side of things has been just one of constant learning.
“We’ve gone through many projects, and we’ve sort of come to a happy point now where we do have a very thorough understanding of what works and what doesn’t,” he says.
“There is a case for all types of different green infrastructure in this, whether it’s a green facade or a green wall or a green roof, all of them have their places, or a place for combining them all in one so you get the best of everything. And that’s totally cool.”